[Info-vax] DZQ11 on VAX/4000 Model 300

[johnwallace4 at yahoo.co.uk]

On Monday, 14 January 2019 21:19:24 UTC, David Wade  wrote:
> On 14/01/2019 17:42, Stephen Hoffman wrote:
> > On 2019-01-14 17:04:41 +0000, David Wade said:
> > 
> >>   I have just installed a DZQ11 in my VAX/4000 and once I figured out 
> >> I had by "A" and "B" pins mixed up on the BERG connector  (I had to 
> >> fabricate a lead as it came without any) on a brief test it seems to 
> >> be working just fine.
> >>
> >> However when I removed it the VAX seemed to hang on boot. I popped it 
> >> back in and it seems to be working fine.
> > 
> >> So should I do anything to VMS to manage its configuration?
> > 
> > Nope.  OpenVMS is working exactly as expected.
> > 
> 
> Why does it hang when the card is removed? Thats not expected to me...
> .. if the CSRs worked before, surely they work the same afterwards....
> 
> >> In case it matters the machine is running VMS 7.3. The other cards in 
> >> the machine are, from the CPU and memory moving left, a TK70 
> >> controller card, a KZQSA SCSI controller with CD ROM and the DZQ11.
> >>
> >> Please excuse me asking on here but google seems to be intent on 
> >> referring me to hpe sites which all redirect to the documentation Index.
> > 
> > HPE is exiting the OpenVMS business.
> > 
> 
> Then why does it still have the documentation catalogue ...
> 
> > Use Google Groups search of the comp.os.vms newsgroup archives, search 
> > for the word "serpentine" (though that's less of an issue with BA213 and 
> > BA215 and BA4xx series Q-bus boxes), and learn how the Q-bus and the 
> > Q-bus boards are configured.
> > 
> 
> The BA440 backplane isn't a serpentine plane is it?
> 
> > Basically, the Q-bus CSRs and vectors can vary by what's installed in 
> > the Q-bus in the box, and you'll need to adjust the CSR and (if present) 
> > vector settings on one or more other Q-bus modules in the bus, and/or 
> > insert a bus grant card or otherwise fill the vacated slot.
> > 
> > Start by reading chapters 3 and 4 here:
> > https://archive.org/stream/bitsavers_decvax630AITechnicalManualBA23EnclosureOct85_15635013/AZ-GLFAB-MN_VAXstation_II_Technical_Manual_BA23_Enclosure_Oct85#mode/2up 
> > 
> 
> That is a Serpentine backplane isn't it? Frome reading the VAX/4000 
> manual the BA440 isn't a serpentine backplane. The CD slots are seem to 
> be generally only used for memory and there is no
> 
> > 
> > Oh, and ********NEVER********** believe the interrupt vector setting 
> > shown by OpenVMS.   Be skeptical about the CSR setting, too.
> > OpenVMS VAX will tell you what it thinks or expects the vector to be, 
> > and that may not match reality.
> > OpenVMS VAX has no direct means of reading the interrupt vector setting, 
> > and the indirect means is dicy at best and is not implemented by OpenVMS 
> > displays.
> > Again, ********NEVER, EVER, EVER, UNDER NO CIRCUMSTANCES, DO NOT EVEN 
> > THINK OF IT, NOT-AT-ALL, NOPE, DO NOT MAKE THIS MISTAKE******** trust 
> > what OpenVMS VAX shows for CSR and particularly vector settings.
> > Remove the boards, and decode the CSR and (if present) the interrupt 
> > vector setting.
> > 
> > And FWIW, Google seemingly doesn't include the Google Groups content in 
> > most Google searches.  Only the Google Groups search seemingly includes 
> > that data from here in the newsgroup, and that Google Groups search 
> > doesn't always work reliably.
> > 
> > 
> >
> It sometimes pops up....
> 
> Dave..

Without seeing some more info on what happens in the (failed)
boot process it's hard to be helpful. Are you using a serial 
console whose output can be captured and posted somewhere?

Also there is no such thing as VAX/4000, there are various 
VAX 4000 family members of different shapes and sizes and 
capabilities. 

To the best of my recollection very few (none?) of them were 
sold in a BA23-type box with the BA23-associated mixed Q/CD 
backplane. See e.g.
https://en.wikipedia.org/wiki/VAX_4000 

Also look elsewhere on t'Interweb for references to BA440 
enclosure which was frequently used for VAX 4000, (or even 
look at the manufacturer label on your own enclosure) so
readers can have a better idea of what's in the box, which 
should help provide better responses to your questions.

Is there any chance that the addition of the DZQ card in the
"VAX/4000" has done something which persists after the card 
is removed? As you rightly point out, it's not unreasonable 
to expect the "orignal" behaviour to be restored when the 
DZQ is removed, if it's purely related to CSRs and vectors
etc. However...

Let's suppose (for example - not suggesting that this is
what's happening here, insufficient data to rule it in or 
rule it out) the insertion of the DZQ makes something visible 
that was previously invisible. 

Also suppose that newly visible something is VMScluster-related 
and contributed to votes (lots of VAX 4000 systems had DSSI
connected storage. DSSI disks could and did sometimes 
contribute to cluster votes, and in the right circumstances
that change could lead to an increase in E

Suppose also that removing the DZQ makes that something go
away, and that it reappears when the DZQ is put back in, 
either because of changed CSR/vectors or changed grant 
continuity or whatever.

If it's having an effect on cluster formation, votes, etc, 
it ought to be reasonably obvious from a boot-time console 
log, if it was happening. 

Or this could be irrelevant to your setup. Right now it's hard 
to say, but a little more detail on what you've actually got 
might well be useful.

Best of luck. Have a lot of fun.